From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755293Ab0IHOrO (ORCPT ); Wed, 8 Sep 2010 10:47:14 -0400 Received: from cantor.suse.de ([195.135.220.2]:39715 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752931Ab0IHOrM (ORCPT ); Wed, 8 Sep 2010 10:47:12 -0400 Date: Wed, 8 Sep 2010 16:47:08 +0200 From: Jan Blunck To: Andi Kleen Cc: Linux-Kernel Mailinglist , linux-rt-users@vger.kernel.org, peterz@infradead.org, Sven-Thorsten Dietrich , Michael Galbraith Subject: Re: [RFC 3/4] Disable scheduler tick when we are running SCHED_FIFO tasks Message-ID: <20100908144708.GK7436@bolzano.suse.de> References: <1283948964-6418-1-git-send-email-jblunck@suse.de> <1283948964-6418-4-git-send-email-jblunck@suse.de> <87vd6gweo6.fsf@basil.nowhere.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87vd6gweo6.fsf@basil.nowhere.org> Organization: SUSE LINUX Products GmbH, GF Markus Rex, HRB 16746 (AG Nuernberg) User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 08, Andi Kleen wrote: > Jan Blunck writes: > > > This patch is disabling the scheduler tick to go off when there is a task > > with SCHED_FIFO policy running. Since these tasks are not timesliced anyway > > we only care about timers, softirqs and such stuff just like when we disable > > the tick during idle periods. > > How would these tasks accounted for then? > > The CPU time accounting relies on the timer tick currently. > Yes, that is a known issue. Jan > -Andi > > -- > ak@linux.intel.com -- Speaking for myself only.